#include<stdio.h>

double ave(double a[],int n)
{
    double sum = 0;

    for (int i = 0; i < n; i++)
    {
        sum += a[i];
    }
 
    return sum/n;
}

int main(void){ 

 int N;

 scanf("%d",&N);

 double x[N],p; int i; for(i=0;i<N;i++)  scanf("%lf",&x[i]);
 p=ave(x,N); printf("ave=%.2f\n",p); return 0;
}